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Adding Rational Numbers
- To add fractions with unlike denominators write equivalent fractions with a like denominator. Then add the numerators, keeping the denominator the same. Remember to simplify!
- Any common denominator may be used. You can multiply the denominators of two fractions to find a common denominator. However, using the Least Common Denominator (LCD) may save steps and make it easier to simplify the final answer.
- To add rational numbers you can change all numbers to decimals or all numbers to fractions.
[1/4] + [3/5] =
- [5/20] + [12/20]
[17/20]
− [2/3] + [5/7] =
- − [14/21] + [15/21] =
[1/21]
[3/8] + [5/12] =
- [9/24] + [10/24] =
[19/84]
− [3/10] + [8/15] =
- − [9/30] + [16/30] =
[7/30]
Change to fractions to solve. 3.25 + [3/4] =
- 3[25/100] + [3/4] =
- 3[1/4] + [3/4] =
- 3[4/4] =
4
Change to fractions to solve. − 1.2 + 2[17/20] =
- − 1[2/10] + 2[17/20] =
- − 1[4/20] + 2[17/20] =
1[13/20]
Change to decimals to solve. 3[3/5] + 2.7 =
- 3[6/10] + 2.7 =
- 3.6 + 2.7 =
6.3
Change to decimals to solve. − 1.7 + 5[7/20] =
- − 1.7 + 5 + 20| ― 5.00 =
- − 1.7 + 5.35 =
3.65
Change to fractions to solve. 4[7/30] + 1.8 =
- 4[7/30] + 1[8/10] =
- 4[7/30] + 1[24/30] =
- 5[31/30] =
6[1/30]
Change to fractions to solve. − 2.3 + 1[1/8] =
- − 2[3/10] + 1[1/8] =
- − 2[12/40] + 1[5/40] =
− 1[7/40]
A recipe calls for 2[2/5] cups of sugar, 3[9/10] cups of flour, and 1[4/15] cups of chocolate chips. How many cups of materials does the recipe need?
- 2[2/5] + 3[9/10] + 1[4/15] =
- 2[12/30] + 3[27/30] + 1[8/30] =
- 6[47/30] =
7[17/30] cups
*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.
Answer
Adding Rational Numbers
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